Assignments of backbone 1H, 13C and 15N resonances in H-Ras (1–166) complexed with GppNHp at physiological pH

The small GTPase Ras is an important signaling molecule acting as a molecular switch in eukaryotic cells. Recent findings of global conformational exchange and a putative allosteric binding site in the G domain of Ras opened an avenue to understanding novel aspects of Ras function. To facilitate detailed NMR studies of Ras in physiological solution conditions, we performed backbone resonance assignments of Ras bound to slowly hydrolysable GTP mimic, guanosine 5′-[ß, γ-imido]triphosphate at pH 7.2. Out of 163 non-proline residues of the G domain, signals from backbone amide proton, nitrogen and carbon spins of 127 residues were confidently assigned with the remaining unassigned residues mostly located at the exchange-broadened effectors interface

Timely Student Feedback

Students are not only interested in their grades but they are also interested in feedback (Mulliner & Tucker, 2017), as this is an important element of their learning cycle (Gibbons et al., 2018). Together with lecturers they agree that for this to be effective, it must be returned quickly so that it can be acted on within the context of their learning (Denton et al., 2008; Mulliner & Tucker, 2017). However, the delivery of timely and effective feedback can be a burden on lecturers, particularly if they are responsible for large classes and in the early stage of their career. These and similar challenges contribute towards the low approval ratings on feedback provided by students across our national third-level institutions (Gibbons et al., 2018). This report explores the benefits and functionality of alternative applications that can help address these challenges and give feedback (1) within class, using TurningPoint, (2) within one to two weeks, using Peergrade, and (3) up to fifteen working days, using the virtual learning environment (VLE) Brightspace. These timeframes have been chosen as research suggests that a policy of providing feedback with fifteen working days can increase student satisfaction (Mulliner & Tucker, 2017). The benefit of these applications for both student and lecturer are established here and a poster artefact has been developed to provide a condensed summary of the applications along with additional resources to help ensure their successful implementation

In Vitro Evaluation of the Cytotoxicity of a Folate-modified β-cyclodextrin as a New Anti-cancer Drug Delivery System

Many chemotherapeutic drugs are therapeutically non-selective and do not distinguish between healthy cells and tumour cells which can result in severe side effects and toxicity. Drug delivery systems can be used to target specific cells and therefore may eliminate many of the side effects, increasing drug efficiency and efficacy, and controlling drug release. One possible strategy for targeted drug delivery is to use unique molecular markers such as folate receptors in cancer cells. In this work the cytotoxicity of a novel cyclodextrin-folate conjugate, 6-deoxy-6-[(1-(-2amino)ethylamino)folate-β-cyclodextrin (CDEnFA) was studied using the MTT assay and the MCF-7 (Breast), HeLa (Cervical), A549 (Lung cancer) and BEAS-2B (normal Lung) cell lines. The MTT assay showed that the drug delivery vehicle CDEnFA is not cytotoxic towards the cell lines studied even towards the normal BEAS-2B cell line and therefore it is expected that it is safe for medical use. The inclusion complex CDEnFA:MTX has superior cytotoxic activity towards all of the cancer cell lines studied compared to the drug MTX alone and CDEnFA:MTX is four times less cytotoxic than the drug towards the normal cell line. The observed toxicity is attributed solely to MTX since CDEnFA did not exhibit significant cytotoxicity. These results also suggest that the drug remains bioactive even after inclusion in the CD cavity. The cytotoxicity trend observed for CDEnFA:MTX in this study is MCF-7 (Breast) \u3e A549 (Lung) \u3e HeLa (Cervical) \u3e BEAS-2B (normal Lung)

Analysis of Binding Site Hot Spots on the Surface of Ras GTPase

We have recently discovered an allosteric switch in Ras, bringing an additional level of complexity to this GTPase whose mutants are involved in nearly 30% of cancers. Upon activation of the allosteric switch, there is a shift in helix 3/loop 7 associated with a disorder to order transition in the active site. Here, we use a combination of multiple solvent crystal structures and computational solvent mapping (FTMap) to determine binding site hot spots in the “off” and “on” allosteric states of the GTP-bound form of H-Ras. Thirteen sites are revealed, expanding possible target sites for ligand binding well beyond the active site. Comparison of FTMaps for the H and K isoforms reveals essentially identical hot spots. Furthermore, using NMR measurements of spin relaxation, we determined that K-Ras exhibits global conformational dynamics very similar to those we previously reported for H-Ras. We thus hypothesize that the global conformational rearrangement serves as a mechanism for allosteric coupling between the effector interface and remote hot spots in all Ras isoforms. At least with respect to the binding sites involving the G domain, H-Ras is an excellent model for K-Ras and probably N-Ras as well. Ras has so far been elusive as a target for drug design. The present work identifies various unexplored hot spots throughout the entire surface of Ras, extending the focus from the disordered active site to well-ordered locations that should be easier to target

Advancing the Future of Nursing: A Report by the Building Academic Geriatric Nursing

In the United States, the number of older adults will double during the next 25 years (United States Census Bureau, 2008). This dramatic demographic shift is changing the landscape of health care practice as more people live longer with multiple chronic conditions. To better prepare nurses to care for this future population, the John A. Hartford Foundation partnered with the American Academy of Nursing in 2000 to launch the Building Academic Geriatric Nursing Capacity (BAGNC) program. Since that time, 251 scholarships and fellowships have been awarded to nurses to advance geriatric nursing education, research, and practice. In 2009, the BAGNC nurse scholars and fellows formed an alumni organization to expand and continue their leadership development through peer networking and mentored policy initiatives. The BAGNC Alumni organization represents an elite set of new leaders in gerontological nursing to advance geriatric nursing education, research, and practice (Fagin, 2012). To this end, at the 2011 Council for Advancement of Nursing Science\u27s Special Topics Meeting, the BAGNC Alumni presented their ongoing and completed projects that relate to the Institute of Medicine (2011) (IOM) report The Future of Nursing: Leading Change, Advancing Health. Summaries of the individual presentations from this panel addressed the four key IOM messages and are presented in this article to highlight the action of these scholars and fellows

Synthesis, characterisation and DNA intercalation studies of regioisomers of ruthenium (II) polypyridyl complexes

Regioisomers of the functional group of the main ligand (L) on a series of [Ru(phen)2L]2+and [Ru(bpy)2L]2+ complexes, where phen is 1,10 phenanthroline and bpy is 2,2′-bipyridine, were synthesised to investigate the interaction with deoxyribonucleic acid (DNA) as potential therapeutics. UV–Vis binding titrations, thermal denaturation and circular dichroism were used to evaluate their interaction with DNA. The conclusions indicated the significance of the auxiliary ligand; especially 1,10-phenanthroline has on the binding constants (Kb). The systematic variation of auxiliary ligand(phen or bpy), and polypyridyl ligand (4-(1H-Imidazo[4,5-f][1,10]phenanthrolin-2-yl)benzonitrile (CPIP), 2-(4-formylphenyl)imidazo[4,5-f] [1,10] phenanthroline (FPIP), 2-(4-bromophenyl)imidazo[4,5-f][1,10]phenanthroline (BPIP) and 2-(4-nitrophenyl)imidazo[4,5-f] [1,10] phenanthroline (NPIP), split in terms of functional group change were investigated for DNA interaction. The CPIP analogues in particular were investigated for the regioisomerism (ortho, meta, para) effect of the nitrile group on the ligand. It was found that both the DNA interaction could be tailored through the systematic variation of the electronic nature of the individual auxiliary ligand and to a lesser extent the functional group and regioisomeric change. Preliminary cell line studies have been carried out to determine the selectivity of the complexes against cell lines such as A375 (Skin Cancer), HeLa (Cervical Cancer), A549 (Lung Cancer), Beas2B (Lung Normal Cell) and MCF-7 (Breast Cancer). Complexes which had strong DNA interactions in the binding studies have proven to be the most efficacious against certain cell lines. Establishing well-defined structure property relationships when looking at trends in spectroscopic properties and DNA binding will aid in the intelligent design of potential therapeutic complexes